#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c;
  cin >> a >> b >> c;
  /*  vector<char> s;
   s.push_back(a + '0');
   s.push_back(b + '0');
   s.push_back(c + '0'); 
   */
  string s = to_string(a) + to_string(b) + to_string(c);
  sort(s.begin(), s.end(),greater<char>());
  // reverse(s.begin(), s.end());
  cout << s;
  return 0;
}